By mid-2026, the only accepted paths are calculating tonnage using Transport Canada’s Simplified Method (Form 4A) or hiring a certified marine measurer, and most boats over roughly 25 to 28 feet will reach at least 5 net tons once measured properly. This matters for Canada boat registry eligibility, mortgages, and international travel, as well as much more.
The 2026 Shift Away From the Tabular Method
For years, owners of boats under 12 metres relied on a shortcut that estimated tonnage based on length alone. That approach is no longer accepted.
Until July 1, 2026:
- Boats under 12 metres could use a tabular method
- Length alone could determine tonnage
- An 8.5-metre boat could be treated as measuring 4.99 tons
- No depth or breadth calculations were required
As of mid-2026:
- The tabular method is no longer valid
- Owners must use Form 4A, the Simplified Method
- Alternatively, a professional measurer can be hired
- Actual dimensions now control the tonnage result
We guide boat owners to the correct Transport Canada forms so they can meet current Canada boat registry requirements without relying on outdated tables.
Gross Tons and Net Tons Explained Simply
Net tonnage and gross tonnage are often confused, but they measure different things.
Gross Tonnage
Gross tonnage reflects the overall internal volume of the boat. Remember that it:
- Is not a measure of weight
- Includes enclosed spaces below and above deck
- Reflects the physical size of the boat
- Is used as a starting point for other calculations
Net Tonnage
Net tonnage reflects usable space related to earning capacity. It:
- Excludes engine rooms and certain service spaces
- Focuses on areas used for passengers or cargo
- Is always less than gross tonnage
- Determines whether key registration thresholds are met
When owners ask us whether their boat is over 5 net tons, the answer almost always depends on proper measurement, not guesswork or length alone.
The “Magic Number” and What It Means for Your Boat
The 5 net ton mark is a turning point for many owners. Once this threshold is reached, certain registration options become available through the Canada boat registry, and others may no longer apply.
- Most boats over 25 to 28 feet reach this threshold
- Cabin layouts often push net tonnage higher than expected
- Deeper hulls increase both gross and net tonnage
- Enclosed spaces count even if rarely used
Measuring Tonnage Using the Simplified Method
The Simplified Method does not require advanced technical training, but it does require precision.
You will need three measurements:
- Length (L)
- Measured from the stem to the stern post
- Breadth (B)
- Measured at the widest point of the hull
- Depth (D)
- Measured from the top of the deck to the bottom of the keel
These measurements are entered into a formula provided by Transport Canada.
- Gross tonnage is calculated first
- A hull-shape coefficient is applied
- Net tonnage is derived by excluding certain spaces
How 15 Gross Tons Fits Into the Picture
Some owners focus on the 5 net ton figure and overlook gross tonnage.
- 15 gross tons is another key threshold
- Boats approaching this size often exceed 5 net tons as well
- Larger beam and depth increase gross tonnage quickly
- Multi-deck boats reach this level sooner than expected
Knowing both numbers helps avoid surprises during registration or inspection.
How Tonnage Affects Canada Boat Registry Options
Tonnage determines which registration paths are available.
Small Boat Registration
For owners exploring small boat registration options:
- Tonnage determines eligibility
- Boats under certain tonnage limits may qualify
- Exceeding 5 net tons can change available paths
- Accurate measurement prevents rejected applications
We help owners identify which forms align with their tonnage and intended use within the Canada boat registry system.
Pleasure Craft Licence and Tonnage
A pleasure craft licence serves a different purpose than registration. It:
- Identifies a boat for recreational use
- Does not establish formal title
- Does not support marine mortgages
- Is not interchangeable with registration
Tonnage still matters because owners often transition away from a pleasure craft licence once their boating needs expand.
Registration Transfer and Measured Tonnage
We provide the forms needed to keep registration details aligned with Canada boat registry standards during ownership changes. When ownership changes, tonnage remains part of the boat’s official profile.
- A registration transfer relies on existing tonnage data
- Incorrect measurements can delay processing
- Updated measurements may be required after refits
- Accurate tonnage protects buyers and sellers
Government Boats and Tonnage Measurement
Certain boats owned or operated by public bodies follow specific rules.
Registration of a Government Vessel
For registration of a government vessel:
- Tonnage must still be calculated accurately
- Measurement standards do not disappear
- Gross and net tonnage still apply
- Proper forms remain required
International Travel and Cross-Border Planning
Boat owners planning to travel outside Canada often encounter tonnage questions.
- U.S. and Caribbean authorities expect clarity
- Registered boats face fewer border issues
- Clear tonnage certificates reduce delays
- Measurements support proof of eligibility
Financing, Mortgages, and Tonnage
Lenders rely on formal registration details.
- Marine mortgages require registered boats
- Registration requires verified tonnage
- Informal estimates are not accepted
- Proper measurement supports financing timelines
Legal Framework and Measurement Standards
Tonnage rules do not exist in isolation.
- They align with Canadian maritime laws
- Measurement standards are set nationally
- Forms reflect current legal requirements
- Changes like the 2026 shift are law-driven
Common Misunderstandings About Boat Tonnage
We regularly see the same misconceptions.
- Length alone no longer determines tonnage
- Weight has nothing to do with tonnage
- Older certificates may not reflect current rules
- Renovations can change tonnage results
Clearing up these points helps owners avoid unnecessary delays with the Canada boat registry.
How We Support Your Tonnage and Registration Goals
Our service focuses on access and clarity. We:
- Provide the official forms used for measurement
- Align those forms with current registry requirements
- Help owners choose the correct path based on tonnage
- Simplify interaction with the Canada boat registry process
We do not measure boats or gather documents on your behalf, but we make it easier to use what you already have to move forward confidently.
Frequently Asked Questions About Measuring 5 Net Tons
Is my boat automatically under 5 net tons if it is under 12 metres?
- No
- Length alone no longer controls tonnage
- Depth and breadth can push net tonnage higher
Do open boats count enclosed space differently?
- Open decks reduce enclosed volume
- Cabins and fixed structures still count
- Each design must be measured individually
Can refits change my tonnage?
- Yes
- Added cabins increase tonnage
- Structural changes may require re-measurement
Is professional measurement mandatory?
- Not always
- Form 4A is acceptable for many boats
- Complex designs may still require a measurer
Staying Aligned With Current Registry Expectations
The shift away from tabular estimates changed how owners approach registration.
- Accuracy is now essential
- Assumptions lead to rejected filings
- Proper forms save time
- Clear tonnage supports long-term plans
At our portal, we provide access to the right Canada boat registry forms and guidance.